<?php
/**
 * Created by IntelliJ IDEA.
 * User: Administrator
 * Date: 2019/7/25
 * Time: 16:05
 */
function guid()
{
    if (function_exists('com_create_guid')) {

        return com_create_guid();

    } else {

        mt_srand((double)microtime() * 10000);//optional for php 4.2.0 and up.

        $charid = strtoupper(md5(uniqid(rand(), true)));

        $hyphen = chr(45);// "-"

        $uuid = chr(123)// "{"

            . substr($charid, 0, 8) . $hyphen

            . substr($charid, 8, 4) . $hyphen

            . substr($charid, 12, 4) . $hyphen

            . substr($charid, 16, 4) . $hyphen

            . substr($charid, 20, 12)

            . chr(125);// "}"

        return $uuid;

    }

}